Douglas B. Tumminello

Douglas B. Tumminello

Managing Partner of the Colorado Offices vCard
303.623.9222 fax
1200 Seventeenth Street
Suite 3000
Denver, CO 80202

Doug Tumminello is a trial lawyer who represents companies in civil lawsuits ‎involving significant financial or reputational exposure. His practice focuses on complex business, business tort, and intellectual property litigation, including matters ‎involving claims against consumer product companies and outdoor recreation companies. He represents a ‎variety of well-known business and non-profit entities as litigation and ‎trial counsel and has tried cases in the state and federal courts of Colorado and Wyoming as well as in ‎private arbitrations, and has argued before Colorado and federal ‎courts of appeal. Doug’s litigation experience includes contracts, real estate, negligence and intentional acts, products liability, supply chain, intellectual property, waiver/exculpatory contracts, and insurance-related claims. Doug regularly advises businesses concerning formation, corporate governance and compliance, risk management and strategic planning issues.

Doug is the Vice-Chair of the Colorado Bar Association’s Military & Veterans Affairs Section and chair’s the section’s monthly pro bono legal clinic “Colorado Lawyers for Colorado Veterans.” The clinic serves the various legal requirements of indigent military veterans throughout Colorado by pairing the veterans with attorneys willing to work on a pro bono or needs-based basis.

Doug is also the Managing Partner of the firm’s Colorado Offices (Denver and Colorado Springs) and serves as Chair of the firm's Sports and Outdoor Recreation industry team. Doug is also an extreme adventurer who has summited Mt. Everest ‎and set world records for rowing a row boat 3,600 miles across the ‎Indian Ocean from Australia to Mauritius. Most recently he attempted to ski solo and unsupported from the coast of Antarctica to the South Pole, although his attempt was thwarted by weather and injury. He is a well-regarded ‎national speaker and has given a number of keynote addresses to ‎business, civic and nonprofit organizations, schools and churches.

Professional Experience

  • Lewis Roca Rothgerber Christie LLP (legacy firm Rothgerber Johnson & Lyons LLP), 1996-Present
  • United States Army, Infantry Officer, 1987-1992

Memberships & Affiliations

  • The Explorers Club, Member
  • Sherpa Memorial Foundation, Board of Directors and President
  • Himalayan Rescue Association USA, Board of Directors
  • Yampa Valley Gives, Board of Directors
  • Military & Veterans Affairs Section Colorado Bar Association, Vice-Chair
  • Denver, Northwestern Colorado, Colorado and American Bar Associations, Member
  • 14th Judicial District, Colorado, Judicial Performance Commission
  • City of Steamboat Springs, Colorado, Parks and Recreation Commission

Representative Matters

  • Trail counsel for defendant in federal court lawsuit seeking multimillion dollar award for alleged sexual assault.  Prevailed following jury trial.
  • Trial counsel for client regarding contract claims. At trial, successfully defended the claims brought against his client and prevailed on all counterclaims against the plaintiff, resulting in a $7.6 million trial judgment in favor of his client.
  • Trial counsel for a national company in private arbitration over breach of contract and business tort claims. At arbitration, prevailed on all of the claims brought against his client, and on his client’s counterclaims against the plaintiff, which then resulted in a settlement favorable to his client.
  • Arbitration counsel for national youth sports camp company in litigation over sale of the company, resulting in favorable settlement prior to arbitration hearing.
  • Counsel for real estate investment trust over breach of contract related to sale of medical office complex.  Case settled favorably the week prior to jury trial.
  • Counsel for a national real estate investment trust, defending claims of asbestos exposure at an apartment complex. Successfully defended the claims brought by over 150 plaintiffs, which the plaintiffs estimated to be in excess of $24 million, and obtained a complete summary judgment dismissal of all claims.
  • Trial counsel for insurance holding company and its subsidiaries in bad faith and breach of contract lawsuits in Colorado and Wyoming federal and state courts.
  • Counsel for client in connection with cold weather injury claims sustained during wilderness therapy program.
  • Counsel for national ski resort company in business tort claims resulting from real estate development.

Related News

Outdoor Industry Association partners with Lewis Roca Rothgerber Christie
Agreement offers exclusive access to array of cost-effective legal services for OIA members
Pro bono service awards presented by Lewis Roca Rothgerber Christie
Annual awards honor memory of lawyer dedicated to equal justice and professionalism

Related Events

Past Events
Hop Culture Meet and Greet
Lewis Roca Rothgerber Christie's Liquor Law Group is partnering with client, Hop Culture


  • Presenter, "Combating Product Counterfeiters," Outdoor Industry Association (OIA) Webinar, January 2020
  • Presenter, "Understanding Product Liability Risks," Outdoor Industry Association (OIA) Webinar, September 2019
  • Co-Presenter, “Solving the International Expansion Puzzle – Sustain Your Company’s Global Footprint and Expand Your Business Into Key Markets,” Outdoor University, Outdoor Retailer Summer Market, June 2019
  • Co-Presenter, "Intellectual Property Quiz Show," Outdoor University, Outdoor Retailer Summer Market, July 2017
  • Presenter, Keynote presentation, National State Auditors Association, June 15, 2016
  • Speaker, “Emerging Corporate Compliance Trends & Predictions,” Association of Corporate Counsel, April 20, 2016
  • Presenter, “Intellectual Property, Manufacturing and Sales Warranties, and Liability Waivers in the Outdoor Manufacturing and Services Industry,” Yampa Valley Entrepreneurship Center, March 25, 2016
  • Presenter, Keynote presentation, Medtronic, Inc. Sales Team, 2015
  • Presenter, Keynote presentation, IMA Financial Group, 2015


  • "VF Corp Taking Its Talents to Denver," Law Week Colorado, 8/29/2018
  • Author, "Impact of the Outdoor Economy," Steamboat Pilot & Today, 5/14/2018
  • Author, "The REC Act and the Rise of the Outdoor Recreation Economy," Law Week Colorado, March 7, 2017
  • Author, "Ride Your E-Bike Wherever You Want? Think Again.," Law Week Colorado, September 10, 2016
  • Author, "Pretrial Publicity in Criminal Cases of National Notoriety," 46 Am. U. L. Rev. 39 (1996)


  • The Best Lawyers in America - Commercial Litigation, Product Liability Litigation - Defendants, 2020-2021
  • Colorado Super Lawyers - Business/Corporate, Business Litigation, 2019-2020

Other Info



J.D., University of Denver, Sturm College of Law, 1996, Order of St. Ives
B.S., United States Military Academy, West Point, 1987

Bar Admissions


Court Admissions

Colorado Court of Appeals
Colorado State Judicial District Courts
Colorado Supreme Court
U.S. Court of Appeals, Tenth Circuit
U.S. District Court, Colorado
U.S. District Court, Wyoming
U.S. Supreme Court
Wyoming State Courts
Wyoming Supreme Court